1. Field of Invention
This invention generally relates to electronic devices having hinges and, more particularly, to those hinges also serving as conductors for providing electrical paths between hinged means.
2. Description of Related Art
Portable computers are common in the market today. These portable computers, often referred to as notebook and sub-notebook computers, are versatile in that these computers may be used in "mobile" locations without AC power such as within a bus or an airplane. Because of their portability, weight and size are important considerations for their designs. As a result, a portable computer typically has a display housing brakingly engaged to a main body housing via one or more hinges enabling the two housings to fold against each other for ease of transport. But when in use, an optimal angle between the housings can be similarly rotably adjusted for user operations.
A problem for these portable computers is electromagnetic interference. Electromagnetic interference (EMI) or electrical noise disrupts the normal operation of electronic devices. Such disruption may be caused by its external cabling, power supplies, electronic components, display screen and the like. Such a disruption may even be caused by its external environment because an electronic device that radiates electrical noise is also susceptible to electrical noises from other sources. Therefore, ensuring the electronic devices to have a proper EMI shield and associated grounding path is one typical way for reducing the effects of EMI. But for those devices with hinged housings such as portable computers and cellular telephones, the EMI shield grounding path between the two EMI shielded housings is typically implemented in an unsatisfactory manner.
One known method is to make use of specifically configured conductive connectors making contact between the two housing shields. Unfortunately, these connectors themselves are typically susceptible to EMI absorption. Furthermore, they tend to be bulky, heavy and expensive. Another existing method is to use copper cladded and ferrite beaded cables. On the one hand, the extra copper shield on the cables makes the cables too stiff to withstand the rigors of portable computing. On the other hand, the bulk of the ferrite beads uses up premium real estate inside the housing. Furthermore, both of these methods have been used in parallel in the past with limited success.
Therefore, when designing an electronic equipment having hinged housings and where each housing provides EMI shielding, it is desirable for implementing a shield grounding path between the housings in a light, compact, and economical manner. In cases where EMI shields are not in place for those hinged housings having metallic enclosures, it is also desirable to provide a ground path implementation for the housing enclosures.